Press Release

California Water Service Group Schedules Third Quarter 2010 Earnings Results Announcement and Teleconference

SAN JOSE, CA, Oct 14, 2010 (MARKETWIRE via COMTEX) -- California Water Service Group (NYSE: CWT) today announced that its third quarter earnings results will be released after the market-close on Wednesday, October 27, 2010, and its teleconference will be held at 11 a.m. EDT on Thursday, October 28, 2010.

All stockholders and interested investors are invited to listen to the teleconference. The 2010 third quarter conference call may be accessed by dialing 1-866-253-6505 and keying in ID# 1484282. A replay of the call will be available from 2:00 p.m. EDT on Thursday, October 28, 2010, through December 27, 2010, at 1-888-266-2081, ID# 1484282. The call, which will be hosted by Vice President and Chief Financial Officer Martin A. Kropelnicki and President and Chief Executive Officer Peter C. Nelson, will also be webcast under the investor relations tab at www.calwatergroup.com.

California Water Service Group is the parent company of California Water Service Company, Washington Water Service Company, New Mexico Water Service Company, Hawaii Water Service Company, Inc., CWS Utility Services, and HWS Utility Services, LLC. Together these companies provide regulated and non-regulated water service to more than 2 million people in 100 California, Washington, New Mexico, and Hawaii communities. Group's common stock trades on the New York Stock Exchange under the symbol "CWT."

Contact:
Shannon Dean
(310) 257-1435

SOURCE: California Water Service Group